The conventional hot-fillable blow-molded PET container is generally characterized by a body portion having a series of identical, vertically-elongate vacuum flex panels disposed in spaced relation about its periphery for accommodating volumetric shrinkage in the container due to the vacuum created after the container has been hot-filled with liquid, capped and cooled to ambient temperature. The upper portion, or dome, of the container has been generally characterized by a circular cross-section having a waist. Some people use the waist to grip the container for pouring with one hand, but this is not satisfactory because the waist is too large to be gripped readily. A stepped dome is easier to grip, but does not facilitate pouring from the container because it is too far from the filled container center of gravity.
At present, it has been necessary to make the vacuum flex panels relatively long in order to accommodate the amount of vacuum induced shrinkage required to provide a commercially satisfactory container. Examples of such containers are disclosed in the following U.S. patents owned by the assignee of the present application: D366,416; D366,417; D366,831.
Efforts have been made to incorporate grips in hot-fillable containers to afford both ease of pouring and to accommodate the vacuum induced shrinkage of the container. An example of such a container manufactured by the assignee of the present application is disclosed in the following U.S. Pat. Nos. D344,457; 5,392,937; and 5,598,941.
The aforementioned containers have certain advantages and certain disadvantages. The conventional vacuum panel has the advantage of enabling relatively large size containers with large labelable areas to be produced; however, it has a disadvantage of making such containers difficult to handle. Grip panel containers, on the other hand, have the advantage of providing relatively easy pourability for certain sizes; however, grip panels are difficult to provide in large size containers, and labelable areas are reduced. It is apparent, therefore, that there is a need for a blow-molded plastic container that provides both the ready gripability and pourability afforded by grip-panel containers while providing large labelable areas and avoiding the limitations associated with conventional vacuum-panel containers.